Slayer

You are master at slaying monsters. The very scent of blood is enough to empower your strikes. You gain the following benefits:

• Increase your Strength, Dexterity or Constitution score by 1, to a maximum of 20.
• When you hit with a bloodied enemy (half health or below rounded down) with an attack using a simple or martial weapon, you can choose deal double damage on all of weapon’s damage dice for that attack. Once you use this ability, you can’t use it again until you finish a long rest.
• Whenever you kill a creature with a simple or martial weapon you gain advantage on all weapon attacks for the rest of the round.